Hydrothermally treated vermiculites: Ability to support products for CO2 adsorption and geological implications
Metadata
Show full item recordEditorial
Elsevier
Materia
Vermiculite Expansion treatment Hydrothermal treatment Vermiculitization Carbon dioxide
Date
2022-12-15Referencia bibliográfica
Celia Marcos, Ayoub Lahchich, Pedro Álvarez-Lloret, Hydrothermally treated vermiculites: Ability to support products for CO2 adsorption and geological implications, Applied Clay Science, Volume 232, 2023, 106791, ISSN 0169-1317, [https://doi.org/10.1016/j.clay.2022.106791]
Sponsorship
Ministry of Science and Innovation, Spain (MICINN) Spanish Government PCI2019-111931-2; European Regional Development Fund (ERDF) - Next Generation / EU programAbstract
The proposal of this research was to obtain products with higher porosity and specific surface area than the raw
vermiculite for its possible application as a support material for CO2 adsorption. In addition, it was proposed to
analyze the possible geological implications of the products resulting from the hydrothermal treatment of vermiculites
in relation to their genesis. Hydrothermal treatment in the presence of CO2, at low temperature and
pressure conditions, was carried out in two vermiculites from Uganda and China, with different behavior to
thermal exfoliation and microwave irradiation. The untreated and treated samples were characterized by several
techniques: X-ray diffraction (XRD) for obtaining the mineral composition; thermogravimetry (TG - DTG) for
analyzing the thermal behavior; and BET isotherms for obtaining textural parameters. In addition, the hydrothermal
solutions were characterized by the pH and the measuring of the lixiviated elements with inductively
coupled plasma mass spectrometry (ICP-MS). Vermiculite can be a suitable support for CO2 adsorbents, based on
the SBET and Qm values, and it is susceptible to carbonation. The hydrothermal treatment produced water loss in
the expanded vermiculites by CO2 replacement; as consequence, amorphization occurred in the purer Ugandan
sample, and vermiculitization occurred in the less pure sample from China.The vermiculitization process indicates
that the geological origin of vermiculite may be hydrothermal from phlogopite.